<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form onsubmit="return false">
    <textarea  name ="message" style="width: 400px;height: 200px"></textarea>

    <input type="button" value="发送数据" onclick="send(this.form.message.value)">

    <h3>服务端输出:</h3>

    <textarea id="responseText"style="width: 400px;height: 300px" ></textarea>
    <input type="button" value="清空内容" onclick="javascript: document.getElementById('responseText').value=''">
</form>
<script>
    var socket ;
    if(window.WebSocket){
        socket =  new WebSocket("ws://localhost:8899/ws")
        //收到服务器端发送的消息
        socket.onmessage = function (ev) {
            var t = document.getElementById("responseText");
            t.value = t.value+"\n"+ev.data;
        }

        socket.onopen = function (ev) {
            var t = document.getElementById("responseText");
            t.value="连接开启"
        }

        socket.onclose = function (ev) {
            var t = document.getElementById("responseText");
            t.value = t.value+"\n"+"连接关闭";
        }

    }else{
        alert("浏览器不支持websocket")
    }

    function send(message) {
        if(!window.WebSocket){
            return;
        }
        if(socket.readyState == WebSocket.OPEN){
            socket.send(message)
        }else {
            alert("连接未开启")
        }
    }

</script>
</body>
</html>